Backyard Aquaponics: DIY System to Farm Fish & Veggies

Aquaponics gardening is a growing trend that allows families to create a self-sustaining environment that grows vegetables, fruits, flowers and more with as little maintenance as possible.

The first time I was told about aquaponics gardening, I thought it was going to be very dirty and moldy but was pleasantly surprised to find that it wasn’t like that at all. Aquaponics gardens can be as small or as large as you’d like it to be. They create enough food in a small space and require very little maintenance. Below, we’ve outlined a few items to consider on whether an aquaponics garden would work for you.

Best of Both Worlds
The Aquaponic Gardening Community defined aquaponics as the following:

“Aquaponics is a cultivation of fish and plants together in a constructed, recirculating ecosystem utilizing natural bacterial cycles to convert fish waste to plant nutrients. This is an environmentally friendly, natural food-growing method that harnesses the best attributes of aquaculture and hydroponics without the need to discard any water or filtrate or add chemical fertilizers.”

Basically, aquaponics is a food production system. It combines aquaculture (raising animals such as fish, prawns or snails in water) with hydroponics (growing plants in water instead of soil). The goal of aquaponics is to create a fully self-sustaining system of food.

Both aquaculture and hydroponics require a lot of intervention to maintain. For example, in aquaculture, you have to ensure that the waste from the fish is removed before it builds to toxic levels. In hydroponics, one has to continually replenish and balance chemical nutrients or the plant will die. With aquaponics however, the two systems balance each other out to create a self-sustaining environment.

How does it work?
Aquaponics isn’t that hard. Fish produce waste that turns into nitrate and ammonia. If this builds up too much, it hurts the fish. However, this nitrate and ammonia acts as a fertilizer for the plants and prevents the build up. As the plants suck up the nutrients, it cleanses the water for the fish.

Once the system is setup correctly, only small amounts of water are needed to keep the system going. When the water evaporates naturally, it needs to be replaced. The most common fish used in an aquaponics system is tilapia because they require very little maintenance and reproduce very rapidly.

Before You Get Started
Before you start gathering tanks, pumps and fish, there are a few things you need to consider:

Where. Where will your system be located? Many aquaponics systems are portable (might take you a whole afternoon to move it, but still portable) and are great for areas where outdoor gardening is prohibited by seasons. You’ll need to consider how large your system will be and where you can easily house it. Perhaps a greenhouse? A basement with lighting? On another property? All of this depends on how large your aquaponics system will be.

When. Many fish hatcheries won’t ship fish during the winter months. Some plants are hard to establish during colder times of the year. It takes some time to get the bacteria to grow in your aquaponics ecosystem. All of these are considerations on when you’ll be starting your aquaponics system.

Who. Who will be in charge of taking care of the system? Will children be around the system? If so, this may impact how tall you create the system, if it has windows, how often you want to cultivate, etc.

Building the Structure
Before you buy any fish or add water, you’ll want to make sure that your system is built correctly. You can build a basic structure like the one below:

In this design, the grow bed is placed above the fish tank. Water from the fish tank is pumped up into the grow bed. The grow bed to fish tank volume ratio should be equal. If you decide to add another growing bed, you’ll need to add a sump tank with extra water like the image below:

There are a lot of great aquaponics designs out there that are quick, easy and clean. Feel free to share your designs below in the comment section.

Structural Requirements for Tank. When choosing tanks and other materials to build your structure, be sure to pick items that are waterproof and can handle a lot of weight. Gallons of water can add up quickly and weigh down a lot on your structure. Avoid plastic containers too.

You should also use non-toxic, food safe materials. Since you’ll be growing food in this structure, you don’t want to contaminate the food. This means using non-toxic and inert materials to create your structure.

Many people use large 50-, 30-, or 250-gallon tanks to house their fish and other aquaponics materials.

What Kind of Fish Will I Need?
There are a few different types of fish that work well in aquaponic environments. Here are a few:

Tilapia. Tilapia are the most popular aquaponic fish because they are easy to grow, like warm water and do not require high oxygen. They mature very quickly too.

Goldfish. Goldifish, like Tilapia, are very easy to grow and maintain. There are more commonly used by people who don’t eat their fish.

Catfish. In Florida, Tilapia are illegal. So, many people use catfish instead.

What Kind of Plants Should I Grow?
Most any type of plant can grow in an aquaponic environment. In fact, the only ones that don’t grow well in an aquaponic system are plants that require a pH environment much above or below 7.0. So, things like blueberries or azaleas won’t grow very well in a balanced pH environment.

Things like carrots and potatoes will have a harder time expanding into a mature state with aquaponics. Items like salad greens, tomatoes, peppers and strawberries all grow very well in an aquaponics environment.

The plants are usually grown in a rocky structure with water flowing between the rocks.